[67drake]

My GTO has been running hot the last few times I took it out. The faster I drive the higher the temperature creeps up, even just driving around with no hard acceleration.
So figured I’d start with the basics. The coolant that’s in the car is what I put in there back in ‘08 when I dropped the newly rebuilt engine in. I figured it’s long overdue for a good flush of the block and radiator.
Instead of refilling with the 50/50 mix of antifreeze and water, I’d try Water Wetter. I used it back in the 90’s on a hot running car, but don’t know if it actually helped or not. My cars now stay in a heated and A/C shop, so freezing in the winter isn’t an issue.
So, anyone using Water Wetter? Did it help cooling? Anyone hate it? Why?
Thanks!

[grivera]

i tried water wetter sometime back and wasn't impressed. What temp is your engine running? Have you checked your timing/vacuum advance and thermostat to make sure nothing has failed?

[59safaricat]

Originally Posted by 67drake

The coolant that’s in the car is what I put in there back in ‘08 when I dropped the newly rebuilt engine in.

Your cooling system is officially plugged up. Flushing it out will probably not fix the problem. I have a couple of vehicles that don't get more than 500 miles a year of use yet I still drain and refill them every 2 years using 50/50 with distilled water. The radiator cores in them still look brand new 25+ years later. Remember, it isn't solely mileage, it's time. When the coolant mixture enters the radiator, the clock is ticking.

[steve25]

If you like many have not been using distilled water or a 50/50 that’s premixed then try a acid flush since it will not hurt.

Also if you have a thermostatic clutch fan make sure it’s uncoupling when the engine is fully at normal temp and above 35 mph.
Above 35 mph if all is good you then do not need a fan.
If it’s spinning at engine rpm then it’s only blocking air from passing thru the rad.

[67drake]

Originally Posted by grivera

i tried water wetter sometime back and wasn't impressed. What temp is your engine running? Have you checked your timing/vacuum advance and thermostat to make sure nothing has failed?

At 55 it’s about 185. 65mph it’s up over 200. I had my 3.90 rear in there up till about a month ago. I put the original rear with 3.23’s back in, thinking this would help seeing as how I now live in a rural area. Nope, still running hot. That was never a problem living in the city.
Knowing it hasn’t been flushed I know I have to start there anyway. Just wondering if WW is worth trying as long as I’m going to be refilling the system.
Timing is set at 12 initial Mechanical is putting in 24 degrees and vacuum advance is limited to 8-10 degrees. Honestly haven’t checked it lately. Distributor was set up about 10 years ago by a guy up in MN that came recommended. I’ll be checking that and the fan clutch.
Just how do you go about testing the fan clutch? Never checked one honestly.

[gto4ben]

I've used water wetter and did not see any improvement in cooling. I created my own cooling toolkit that works great in my AC equipped stock 67 GTO.

1. Soak the cooling system initially with Evaporust's Thermocure cooling system rust remover & flush. It helped a lot in cleaning the cooling passages of rust and you can drain it from your system and use it as rust remover for your other parts.

2. Flush the system clean and use plain distilled water and Gunk Motor Medic Radiator Anti-Rust & Water Pump Lube. I don't use antifreeze since the weather is always above freezing in Southern CA.. I have a good 15 lb. radiator cap and that raises the boiling pump enough.

3. Every year, check the cooling system's pH to make sure it stays alkaline (>8-8.5). They sell pH strips for this purpose or you can get a pH tester like I did. It also works great to check your aquarium's pH to keep your fish healthy. Please don't keep your fish in the cooling system.

[grivera]

Checking the fan clutch is easy. With the engine cold the fan should freewheel and at temperature it should be difficult to turn the fan. Tested with engine off of course.

[Schurkey]

Failing to install a proper amount of antifreeze gets people in trouble when they forget, and drive to the mountains for a weekend ski-trip; or the weather turns unseasonably cold like the Big Freeze in Texas a couple years ago. Gotta be nuts to not use anti-freeze in a street-driven car.

If you're going to flush the cooling system, be certain to remove the two block drain plugs when you're done. Otherwise you'll trap a gallon+ of flush water in the block. The Pontiacs I've seen use 1/8" pipe thread plugs, most other V8s use 1/4" pipe plugs. Some Buicks don't have removable block drains--Bastages.

I'd like to see a Safety Data Sheet for "Water Wetter" or similar products. Wild Guess: Mild detergent to break down surface tension.

If that were my vehicle, I'd be looking at mechanical causes for high temps. A fresh thermostat is the first that comes to mind, but there's dozens of possibilities.

[steve25]

Just because your water temp may be creeping up to the hot side of things does not mean that the whole motor is that hot.
This is where the use of a Thermal gun can shed a lot of light on things.

Your engine temp might be the hottest right around the general area where your taking the temperature reading at.

Evens coolant is the Bomb so to speak, but it is expensive, yet is cheap insurance to me.

It gets rid of localized steam hot spots within the cooling system that once they start many times can’t be stopped by increasing the pressure rating of the rad cap or moving more coolant thru the motor.

The amount of pressure being made by the boiling can get to be greater then the pressure rating of your rad cap .

When this takes place a bad cycle has already been started and that local hot spot just grows, and can do so to the point of having a full boil over take place.

If you have a local hot spot making 22 lbs of steam pressure and your rad cap is rated for 16 lb then your in for trouble.

Also before you do anything or spend money on anything be sure to check that you have no bubbles in the rad that would indicate cylinder pressure getting into the system.

Evens coolant will not boil so hot spots can not form.

I have had a few early on and see other folks cars with built up motors and still running what was there original ac cooling system pulleys move too much water too fast thru the rad for the heat to get transferred into the air.

This then starts a nasty cycle of escalating engine temps with increasing rpm.

[grivera]

I’ve thought about trying the Evans coolant as it gets great reviews.

As far as a smaller water pump pulley moving the coolant too fast, seems keeping the coolant in the radiator longer also means keeping it in the engine longer where it will pick up more heat.

[steve25]

Yup. The coolant needs to be thought of as the transfer medium between the basic motor and the core of the radiator.

[78w72]

I used water wetter back in the 90's, tried it with a reduced anti freeze mixture about 70/30, water cools better than anti freeze. Cant say I noticed much of a difference but what I did notice after a couple years is a brown slimy substance in the over flow jug & when I drained the radiator, have read a few times about this brown crap from water wetter.

What I use today is a product from hyper lube that is available everywhere including walmart, says it does the same thing for reducing temps only the hyper lube has corrosion inhibitors in it that the original water wetter didnt have. Again, cant say I notice a difference but none of my cars have overheating issues using stock 4 core radiators & clutch fans, or one 500+hp has a 3 core champion aluminum that cools great in all driving & drag racing conditions.

[steve25]

On another Automotive web site a well known and long respected engine builder noted this.

He dyno's with a temp sensor on each. Exh port and stated this finding that he has seen on many engines

Quote, "for every degree of timing that a motor wants and you do not give it you will see the Exh temp go up 30 to. 40 degrees."

That my friends puts a lot of extra heat into the motor real fast, and if your cooling system does not have the reserve handle that rise, well your in trouble!

[59safaricat]

Using "flushes" generally kills a water pump in short order, have a new one on standby if you take that route.

Never use straight water in a cooling system even if the temps don't go down anywhere close to freezing. Antifreeze has corrosion inhibitors and both lubricates and extends the life of seals in the cooling system, particularly the water pump seal.

A fan clutch should engage hard on a cold start and sound like a garbage truck for a minute or so then quiet down. If it doesn't, it's on its way out. If the clutch never disengages after a cold start and sounds like garbage truck constantly, the bearing is locked up.

[78w72]

They make anti corrosion products for cooling systems if one chooses to run pure water or a very strong ration of water... the hyper lube treatment i mentioned is the same basic thing as water wetter but also has corrosion protection.

[tom s]

Can’t say it’s right but a recommendation from a long time racer and engine builder,I run distilled water and a bottle of Waterwetter.My engines don’t over heat and the water looks clean.Flush once a year and refill.FWIW,Tom

[67GTONUT]

I have been using Water Wetter for years with a light concentration of G05 Anti-Freeze ---- I use a refractometer and usually mix my system to about 0-10 degree protection, I never take it out in temps below 40 anyway, and garage in the dead of winter never gets below 35. In my experience, the Water Wetter doesnt help temps...... but the system seems to recover quicker from spirited driving. I usually run 180-190degrees in normal driving..... If I do some hard pulls on a summer day, she might get up to 200-205,,,,, After a quick coast, the temps plummet quickly back down to my "normal" temps. I do think is due to the less surface tension that the Water Wetter provides.

[geeteeohguy]

I would check for a restricted radiator with a pyrometer.
I would check exhaust temps at the heads...caused by retarded timing or lean mixture.
I would verify timing advance.
I would check for excessive lean mixture at cruise.
I would verify water pump function and plate spacing.

All of the above will cause the engine to build more heat than it can shed. Water wetter won't help you, and a fan won't help. My gut tells me it's a restricted radiator.

[67drake]

I drained the system yesterday, then flushed till water ran clear. I added Thermocure Evaporust like was suggested above. I’m going to leave it in a few days and drive it as suggested in the instructions. I figured this should at least help clean the system up. I plan on pulling the radiator after that. I found a real radiator shop listed online today, about 20 miles north of me. Obviously will call tomorrow to see if still in business.
Then I’ll take it from there.
Thanks for the suggestions guys.

[67drake]

Oh, forgot, I do have a pyrometer. I see a 20 degree difference between temperature where the upper hose goes in radiator and lower is 20 degrees cooler at radiator outlet. This was after an hour drive. Lower hose 160, upper 180.